


Accept (No) Substitutes

by Slybrarian



Category: Captain America (Movies)
Genre: Alpha/Beta/Omega Dynamics, Beta Bucky Barnes, Bucky Barnes's Metal Arm, Gangbang, M/M, Mating Cycles/In Heat, Omega Steve Rogers, Past Relationship(s), Sex Toys
Language: English
Status: Completed
Published: 2015-11-22
Updated: 2015-11-22
Packaged: 2018-05-02 08:00:39
Rating: Explicit
Warnings: No Archive Warnings Apply
Chapters: 1
Words: 3,857
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/5240741
Author URL: https://archiveofourown.org/users/Slybrarian/pseuds/Slybrarian
Summary: <blockquote class="userstuff">
              <p>Steve's heat suppressants start wearing off during a mission, and by the time the team gets home it's too late to get back on them. He's resigned to spending a few days up on his couch with a bucket of ice cream and a headache, since it'd be unfair to even think about being around Bucky so soon after his recovery. </p>
<p>For some reason, Bucky seems to have other ideas.</p>
            </blockquote>





	Accept (No) Substitutes

**Author's Note:**

  * For [bravepress](https://archiveofourown.org/users/bravepress/gifts).



> This was written for the Omega Steve fic exchange.

By the time the quinjet was making its approach to the Avengers airfield, Steve was dreading the rough ride that was coming his way.

He had no one to blame but himself, of course. He knew he'd have a heat coming soon. He knew that when he exerted himself, his overactive metabolism burned through drugs even faster than usual. He knew that a four-hour observation mission could turn into a four-day running battle-cum-hostage situation. Throw it all together and it should have been pretty obvious what could happen. 

There Steve was, though, with a warm feeling in his guts warning him that by the next morning he'd be in full-fledged heat. 

He supposed there were worse things to get complacent about than his heat blockers. Once his doctor had gotten his preventative dosage calibrated, he'd gone for years with barely more than a hot flash or two. He'd forgotten just how useful they were and filed them away with other modern conveniences like cell phones, DVR, and The Google. Well, now it looked like he was going to get a chance to try out modern full-power suppressants too, and see if they really were less likely to involve nausea and vomiting. 

The jet barely even shivered as it touched down thanks to Rhodey's steady hand. Certainly it wasn't enough to disturb Bucky from his position at Steve's side. Against Steve's side, rather; he'd been asleep since takeoff and over the course of the first hour had toppled in slow motion until he came to rest against Steve's shoulder. Steve didn't begrudge him the sleep. He'd been awake practically the entire mission, culminating in a multi-hour standoff with him in the middle of it. It had ended with no one dead, even the leader of the Inhuman separatist cell, a fact that Steve had already filed away for later use the next time Bucky had any doubts about the safety of letting him loose in public. 

"Bucky," Steve said. "Hey, Bucky. Buck. Oh, come on." He tried nudging Bucky but he just opened his mouth a little and added some more drool to the slowly spreading stain on Steve's shoulder.

"Maybe you need to give Sleeping Beauty a kiss," Sam said as he walked past, one wingtip trailing on the deck behind him. Steve gave him the finger instead. 

"Seriously, you need to move," Steve said. He poked Bucky in the side, then managed to grab his collar when Bucky yelped and tried to roll out of his seat. 

"Wha' time is it?" Bucky asked, rubbing at his eyes with his right hand. 

"Time for you to find an actual bed," Steve told him. "Come on, let's go, I don't want to see you again until noon. And that goes for the rest of you! Take Friday off and find something that's not work to do this weekend. That includes you, Vision. Go see a ball game or something."

Steve hoped they would all take his advice to heart and clear out, leaving Steve to curl up in a peaceful if pathetic ball on his couch and mindlessly watch the Food Network until his heat burned through its course. It wasn't that he was ashamed of it or anything, or that the team didn't know he was an omega - like everyone else on the planet who'd read an elementary-level biography - but there was a difference between them knowing he sometimes went into heat and them knowing he was in heat right that instant. Thank God for air filtration and soundproof walls that kept the entire building from knowing who was having sex when. 

Naturally, by the time he stopped by the base infirmary, waited out a lecture about timing and side-effects from the night nurse, and reached his quarters, Natasha was lounging in his recliner. 

"Blockers wear off, huh?" she said. 

There was no point denying it. Steve was positive he wasn't giving off any scent yet, but you didn't need to be for the ultimate Soviet intelligence operative to notice. He shrugged.

"It was bound to happen sooner or later."

"How are you going to handle it?"

"You're in charge while I'm indisposed, with Rhodey in tactical command if you have to deploy. Hopefully these things," Steve waved the box of suppressor pills, "can keep me coherent enough to be functional but unless it's an emergency I shouldn't be making any decisions."

Natasha rolled her eyes. "That's not what I meant. There's other options than the pills, you know."

"I'd prefer not to start reenacting scenes from Avenger-themed pornography, and I can't go hit a club unless I want someone tweeting a play-by-play," Steve said, a little more snippily than he intended. Tony in his bachelor days may not have minded rumors involving entire football teams, but Steve liked to at least pretend he still had some privacy. The fact that part of him really liked the idea of heading to the nearest gym or breeding bar just made him even more grumpy.

"You should talk to James."

"He needs to sleep," Steve said. "And the last thing he needs is me filling his head with pheromones."

"He may have a different opinion."

"Maybe if there was time to actually talk about it. It's too late now. Maybe… before the next time rolls around, I'll bring it up." Steve wasn't sure if he was trying to convince her or himself. He'd had months since Bucky's rescue and rehabilitation to bring up the subject, too focused on their friendship and not the baser physical relationship they'd once had. 

"Fine. Just think about it." Natasha stood and stretched. "Anyway. In case you need to scratch the itch, I got you some presents."

A slight inclination of her head drew his attention to the carry-case on his kitchen counter, the sort they usually used to hold guns or alien artifacts. It hadn't been there when they left for the mission.

"Natasha, what's in the box?" Steve asked as she headed for the door. "Come on, what's in the box?"

She didn't answer. After the door slid shut behind her, he cautiously peeked inside and then immediately closed the top again, face burning. He hid it under his bed where it would be in reach, just in case, but no one would ever find it but the cleaning robots. That done, he set his alarm for when he could take the first pill and tried to get some a few hours rest before his heat could come into full force. 

Steve woke with a start some time later. It was still dark outside, the first shades of dawn beginning to creep into the eastern horizon. He'd kicked all his sheets off, his body burning inside. That needy ache that he'd forgotten for so long was thrumming like a plane engine inside him. 

He wasn't alone.

He slid his hand toward the sidearm he had stashed between the mattress and headboard, closer than the shield on the other side of the room, only to stop when a shadow detached itself from the doorway and said, "Are you okay, Steve?"

"Jesus, Bucky," Steve groaned, smacking at his beside table until he found the lamp switch. 

Bucky blinked blearily into the light, barely awake. If anything he seemed a little confused why he was standing there in nothing but his shirt and boxers. His body was less confused, given the obvious bulge straining against the cotton underwear. Steve could feel the first traces of slick in his hole as his own body reacted to the presence of a beta. 

"I'm fine," Steve told him. "Go back to bed." He tried not to stare at the outline of Bucky's cock, and failed miserably. It must have been pretty obvious, too, because Bucky looked down, back up, and inhaled deeply. 

"Shit, you're in heat, aren't you?" Bucky started to smile, only for it to fade away. "Uh… before, we fucked, right? I'm not makin' that up?"

"Yeah," Steve hastily assured him. "Pretty much every time, least until you shipped out."

"Oh. Good. But… never mind. I guess you must have found an alpha by now." Bucky smiled again, but there was too much strain around his eyes for it to be real. "Sam, right? That'd be good. Or Thor? I don't think anyone could complain about losing to-"

"Bucky, stop," Steve said. He fought back the urge to just tear off his clothes and ride him then and there. If he didn't sort this out then and there, who knew when he would. "I don't need an alpha. You're all I ever needed." 

"Yeah, but that was before." He made a little gesture between them, his meaning implied. Before Steve had a body an alpha would want to claim and that would need an alpha to satisfy it; before Bucky was damaged goods. 

"There was only one alpha I ever looked twice at," Steve told him, "and she wouldn't have minded sharing. Now are you going to fuck me or not?"

Something like Bucky's old smirk returned for a moment, even as he stripped off his clothes. "Depends. Are you going to beg for it?"

"When have I ever begged for anything?" Steve said, kicking his briefs off. He rolled onto his hands and knees, presenting his hole to Bucky. "Get with the program, sergeant. Or do I have to draw you a diagram?"

"Jesus, don't start with that," Bucky said. The bed creaked as he climbed behind Steve. "I ever tell you that every time I saw you in that goddamn uniform I about popped the buttons off my pants?"

"You may have mentioned -" Steve said, cutting off with a gasp as one of Bucky's fingers slid inside him, smooth and easy from the plentiful slick welling up in his hole. 

"Fuck," Bucky said. "How is it you're even tighter than you used to be?"

"Exercise." Steve bit his lip to keep from saying more, because even that single slim digit reminded him so badly of what'd he'd been missing for all these years. He needed Bucky's cock and cum more desperately than he'd ever had before. He was not going to fucking beg for it, though, not ten seconds after he boasted about not _oh thank god_. There it was, sliding further and further into Steve's hole, until finally it was a deep as it could go, and even if it wasn't a huge, exaggerated alpha dick straight out of a Tijuana bible it still felt so good that Steve about broke down sobbing.  
It took a few minutes of fumbling to get going, shifting limbs and positions to find the right spot; both of their bodies had changed since they'd done this. At one point Bucky's cock popped right out and it took him a few seconds of slipping and sliding to guide it back in. But once they got going, things just clicked. Seventy-something years on ice or not, it was like riding a bicycle, and long familiarity and instinct took over. 

Bucky fucked him, swift and steady, almost machinelike in his perfect rhythm. Steve groaned in gratitude, every stroke sending waves of satisfaction and the desire for more coursing through his body, and he grinded back against Bucky's hips. Eventually, after ages or maybe just a few minutes, the rhythm breaks and Bucky lived up to his name, bucking once, twice, three times before stopping as his cum shot into Steve's hole, which warmed and tingled as it reacted to the presence of a man's seed inside him. 

Steve grinned, and in a momentary burst of clarity considered making a smart remark. Any man who'd gone without for that long could be expected to come like an overeager teenager, or something like that. Except Bucky was still inside him, still hard, and pretty soon he started to slowly move again. Even in his twenties, randy and eager for a second round at the drop of a hat, he'd never been up again that quickly. 

This time it was faster, harder. Bucky pounded his ass like he'd realized he wasn't going to break Steve. He reached forward, his metal arm pressing Steve's shoulders firm to the mattress while keeping his hips up with the other, all the overpowering strength of an alpha in rut without the uncontrolled roughness. Steve lost himself in the waves of overpowering lust, his universe shrinking to nothing more than his hole and the other points of contact between their bodies. Neither of them said anything, the only sounds in the room the slap of Bucky's hips against Steve's ass and their grunt and moans. Their bodies communicated everything that needed to be passed. 

Finally Steve could feel his own orgasm coming, building up with the inevitability of a thunderstorm. Feeling the growing tension in his body, Bucky bent over him, chest to his back, breath hot on his neck. With a cry Steve came, his untouched cock shooting over and over, and soon Bucky was following his lead and filling Steve's eager hole once more. 

They collapsed beside each other, panting and glistening with sweat, slick, and cum. They were both grinning like loons, too. Steve knew his body was only momentarily satisfied, that they hadn't even reached the end of his first peak yet, but for now he was content to lay there snuggled next to Bucky first the first time in far too long. 

Steve dozed for a while, in and out for a good twenty or thirty minutes, before the growing buzz reaching up his spine forcibly reminded him he was supposed to be awake and trying to get knocked up. He looked at Bucky and got no response, for his was curled up in a little supersoldier ball and sawing an entire forest of logs. As a beta he was attracted and pulled by the scent of Steve's heat, but he didn't naturally synch up the same way an alpha driven into rut. Steve couldn't bring himself to try to wake him, given how exhausted he'd been, and who knew if he could be ready to fuck this quickly anyway. So Steve, pragmatic when he needed to be, fished out Natasha's box.

It was just an unassuming little gun case, really, but the egg-carton padding inside held something slightly more personal that firearms. The dildos, plugs, and vibes inside ranged from innocuous to frightening. The largest was a knotted metal vibrator that looked like it was meant for the Hulk, not a mortal or even augmented man. Back in the day he'd probably had tried it from sheer cussedness and sprained something in the process. For now he chose a different one, a long silicone dildo with a series of rippling bulges, each larger than the last until the final one was almost knot-sized. 

It was cool as it entered Steve's hole, and while it slid in easily thanks to the slick and cum it was firm and unyielding inside him, a far cry from the floppy rubber of yesteryear. The first knob was little more than a teaser, just enough to sharpen his senses. The next couple reach the size of an average beta's cock, and they grow from there. Steve kept working at is, sliding the dildo deeper inside each time, and in turn spreading his hole wider and wider. He closed his eyes and gripped at the sheets with his free hand, not wanting to give in the to temptation to touch his own cock. Each pop of a bulge in or out of his hole was bright spark of pleasure, a reminder of that unique moment when a new cock pressed into him, or an alpha's knot starting to inflate and spread him wide before finally locking up.

"Jesus fucking Christ," Bucky said. Steve looked at him and saw he'd propped himself up on one arm, watching with wide eyes as the dildo pushed in and out. "So desperate for it you can't even wait for it, pal?"

"You know me," Steve grunted. He kept working the dildo harder.

"What would you even do without me or the meds?" Bucky said. Then, a moment later, Steve could all but see the lightbulb appear over his head. "Wait. Waaaaiiit."

"Mmmm?"

"You went into heat," Bucky said, expression focused, either on his memory or Steve's hole or both. "Not at while I was at basic… right after I made sergeant but before the fair."

"Yep," Steve gasped. He'd almost worked the entire toy inside him now, only another couple inches left before the flared base and handle. It felt so damned good to have it reaching deep inside him. 

"You wanted to save up for a present, and missed your suppressants. And then you went down to... to… the Navy Yard?"

"Right around lunch," Steve confirmed. "Stayed there until I rode it all out."

He remembered it well, like it'd just been yesterday, his heat bringing up the memory crisp and sharp. It hadn't been the first time he'd done it, just the first without Bucky there to keep an eye on things. He'd known the risk he was taking in skipping a few rounds at that time of year, asked around with other omegas to find somewhere that close but safe. It was a tavern with a few rooms in the back, a few blocks from the yards, about as clean as you could get without being in one of those uptown clubs, and run by an old beta gal who kept a baseball bat and shotgun full of rock salt behind the counter. He'd barely made it there in time, his underwear already spotted with slick by the time he got stripped down and folded his things into the locker they provided. 

He'd only had to wait a few minutes before the first beta cautiously poked his head inside, drawn by the scent of an omega but unsure if some unbonded alpha had gotten to him first. Seeing they were completely alone he'd dropped his trousers and stepped out of them, took of his shirt, and waited for Steve to get into position before pushing into him; positively a gentleman. A sailor had been next, then a pair of delivery men making a drop-off. And so on, for a few hours, until the first wave of his heat broke and he'd had some time to rest. The owner came in to make sure he got something to eat and drink before it started up again. 

"And the shift change came," Bucky prompted. Steve realized that he'd been half-coherently been narrating and Bucky had been filling in gaps. It was inexplicably hilarious, that they'd apparently stumbled on a new memory aid, but when he tried to laugh the way his body clenched down on the dildo almost made him see stars. 

"A bunch of yard men, right on the line," Bucky continued, because at that point Steve was panting so much he couldn't have strung a sentence together. "Passing by after work, smelling your sweet pussy even out on the street. Come in, drop a load, be home by supper."

Steve nodded frantically. He could remember how they smelled, so much musk and sweat, mixed with metallic sharpness and grease. If the afternoon fucks and been smooth and leisurely, by men with time to spare, these were quick and dirty, the instinctive beta need to get in and out before someone else took his place. A man would open his fly, maybe not even drop his jeans a few inches, and pound him hard and fast. He'd add his cum to that already dripping down Steve's thighs, button up, and leave him open for the next man in the line outside. Not even so much as a hello or goodbye, just grunts and groans, and the occasional satisfied joking between friends that ignored him entirely. 

"Sailors, too, right? And we both know what horny bastards they are."

"Got my second," Steve said. "4F the week before. Thought it was nice. Serve the country somehow."

"Nah, I figure you just wanted something up your hole and I wasn't around to give it to you. That why you never bond with anyone, you little slut?" Bucky asked. "You just can't stand the idea of giving up all that beta cock?"

"You got me," Steve gasped. He was close now, the entire dildo passing through him down, erratic and uncontrolled. He could barely even keep his arm moving, til Bucky reached down and took over for him. "But at the end.

"An alpha took ya, right?" 

Steve nodded, haltingly finished the story with Bucky's coaxing. A grizzled master chief, greying around the temples, cocky and self-assured in a way alphas half his age could only dream of, the same swagger and confidence that had convinced Steve to stick to Bucky no matter what biology or society said. He'd stripped while the marine using Steve at the moment to finish, a final beta load a trivial insignificant to him, then pulled Steve hard against his chest while pushing his heavy cock inside him. That knot and flood of cum had been enough to finish Steve off.

He'd bought Steve dinner and walked him home, afterward. Being unbonded was no reason to be rude, he'd said. 

"Well, you're an omega, of course you want a knot sometimes," Bucky said, any earlier qualms about competition long gone. "Looks like Natalia left us a few substitutes. Or."

Steve braced himself, knowing that sly look could only spell trouble. 

"Seems like I've already got something that might work."

He lifted that goddamned arm, made a fist. Steve came so hard it was a miracle the building didn't collapse around them. 

For a few minutes, Steve laid there panting, until he worked enough strength back up to roll over and straddle Bucky, whose cock was thick and ready for another bout. He rode him hard until they both came again, by which time Steve's heat had receded. 

"Alright, get up," Steve said, after enough time had passed that cuddling had started to turn from comforting to sticky and a danger to body hair. "Time for a shower and breakfast. We can curl on the couch afterwards." 

"Yeah, yeah, okay, I'm coming," Bucky said. "God, no, not like that, stop smirking. How long do you think this will last?"

"I don't know, I've never been in heat since I took the serum," Steve told him. "Used to over and done with in day after two, maybe three rounds. Now, who knows? Six times? Eight? Three days, a week?"

He was exaggerating, and maybe once his head cleared more he could remember what the doctors had estimated, but it was worth it just to see Bucky's expression. 

"My fucking dick's going to fall off," he groaned, covering his face with a pillow.

Steve grinned and pulled Bucky out of bed. He was vaguely aware that fucking and cuddling all day wasn't exactly a substitute for adult conversation. They'd probably need to talk about feelings and expectations eventually. For now, though, screwing like they were teenagers again was the next best thing.


End file.
